The present invention relates to a magnetic head which can contact a flexible magnetic disk and can record data on the disk and reproduce it from the disk.
Magnetic disks can be classified into two types, i.e., single-sided disks and double-sided disks. Data can be recorded on one surface of a single-sided disk, and on both surfaces of a double-sided disk. A magnetic head device for recording data on double-sided disks and reproducing it from the disk has the structure shown in FIGS. 4 and 5. The device has two magnetic heads 60 positioned one above the other, such that magnetic disk 62 is placed between these heads.
Each magnetic head 60 has two magnetic gaps 63 (i.e., a read/write gap and an erase gap) and a flat surface 61 facing magnetic disk 62. Gaps 63 are formed in this flat surface and located at the middle portion of the flat surface. Head 60 is supported by a support mechanism such that its flat surface is pressed onto magnetic disk 62. This mechanism comprises a gimbal spring and a pivot abutting against this spring. Magnetic head 60 is attached to the gimbal spring. The support mechanism applies a pressure to head 60, thus keeping the flat surface of head 60 pressed on magnetic disk 62. The mechanism allows head 60 to rotate around the radius of disk 62 and also around the line tangent to the circumference of disk 62.
The entire flat surface of magnetic head 60 is kept in contact with magnetic disk 62 by the pressure exerted on head 60 by supporting mechanism. For this reason, gaps 63 are located sufficiently close to disk 62 to record data on disk 62 or reproduce it from disk 62. For the same reason, however, there is a possibility that magnetic disk 62 is worn due to the friction between disk 62 and the flat surface. Thus, the durability of disk 60 is much impaired.
When magnetic disk 62 is rotated at high speed, it generates a great air bearing force, which causes head 60 to float above disk 62. Consequently, gaps 63 are positioned too far from disk 60, and head 60 inevitably fails to record or reproduce data correctly.
When disk 60 is vertically magnetized so that data is recorded on it in high density, it is important that gaps 63 are located sufficiently close to disk 60. In other words, it is desirable that gaps 63 be positioned close to disk 60 and also that the friction between disk 62 and the flat surface of head 60 be reduced as much as possible, thereby to prolong the lifetime of magnetic disk 60.